Dental mallet



. (No Model.)

H. C. HINCHMAN. DENTAL MALLET. 110.462.133. Patented 0ct.2'7,1891.

M L I W.

v n Q W V TTR STATES PATENT Prion..

HENRY CARLISLE lvllNCI-IMAN, OF JOHNSTOlVN, PENNSYLVANIA.

DENTAL MALLET.

SPECFICATION forming part of Letters Patent No. 462,133, dated October27, 1891.

Application filed May 11, 1891.

To @ZZ whom t '1n/ty concern.-

Be it known that l, HENRY CARLISLE Hnvorr MAN, of Johnstown` in thecounty of Cambria and State of Pennsylvania, have invented certain newand useful Improvements in Dental Mallets; and I do hereby declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it pertains tomake and use it, reference beinghadto the accompanyingdraw ings, whichform part of this speclication.

My invention relates to an improvement in engine-mallets for dentists;and it consists in the combination, arrangement, and construction ofparts, which will be fully described hereinafter, and particularlyreferred to in the claims.

The object of my invention is to provide a machine which can be held inthe hand and by means of which a direct positive blow can be given tothe plugger-point and the mallet then thrown back to position, the forceof the blow being regulated by the adjustment of the hand-piece.

Figure l is a side elevation of a mechanism embodying my invention, thecasing being cut away so as to show the different parts. Fig. 2 is asectional View taken at right angles to Fig. 1. Figs. 3 and 4 are detailviews.

A represents the attachment which extends from the dental engine andthrough which the spindle B passes, and which spindle has a pinion Cupon its outer end to engagewith the beveled wheel D upon the main shaftE. The gearings are inclosed in a casingl, which is secured to asupporting-base F, which base has the extension H and the two extensionsG and G', which have their ends journaled upon the shaft E, as shown.

Fastened rigidly tothe shaft E by means of a setserew is a cam J, whichis made to revolve with the shaft for the purpose of operating themallet K and the lever L. Placed loosely upon the shaft E and swingingand moving back and forth thereon is a yoke M, to which the mallet-headK is fastened. This yoke has two openings made through it at rightangles to each other, the one N being made to receive a perforatedsliding block or bearing N to allow the yoke to play back and forth inrelation to the shaft E, and the other one O to allow the cam J to moveSerial Noa 392,331. (No model.)

through for the purpose of operating the mallet. In the opposite end ofthe yoke from the Vmallet is made an opening, and in this opening isplaced a spiral spring P, which is regulated by means of a set-screw Q.'lhe inner end of this spring bears against the block or bearing N andkeeps the block or bearing pressed forward in its openinginthe yoke, sothat the cam will strike the end of the yoke each time it revolves andcause the mallet to strike against the pluggcrpoint and the innerend ofthe hand-piece. Through the end of the mallet-inclosing case ismadeasuitable screw-cap R to enable the operator to regulate the set-screw atwill, and thus regulate the tension of the spring. For the purpose ofreturning the mallet-head to position against the cushion S in the topof the mallet-casing a lever L is pivoted within the said casing, thelower end of which lies in the path of the revolution of the caln and isstruck thereby and turned upon its pivotal point. The upper end of thesaid lever engages the upper end of the mallet and throws it backagainst the cushion S after it has delivered a blow to the plugger, aswill be readily understood. A portion of one revolution ot' the cam isused to operate the mallet for the purpose of giving a direct blow tothe plugger-point, and then the cam strikes the curved lever for thepurpose of moving the mallet back to position, so as to be given anotherblow. The inner end of the pluggerpoint extends inside of themallet-casing in line with the curved path of the mallet K and is placedinside of the hollow hand-piece U, which is screw-threaded at its innerend where it screws into the casing, so as to render it adjustable andthus regulate the force of the blow which is to be given by the malletK. If but an easy blow is desired, the hand-piece is screwed up into thecasing, so that the mallet has but a short stroke; but if a heavy strokeis needed the hand-piece is unscrewed to any desired distance, thusgiving the mallet a longer sweep. The head or inner end of thehand-piece will be protected by means of a leather washer or coversecured to the inner end thereof, so as to protect the hand-piece frominjury and to somewhat soften the blow. The hand-piece U is madetubular, and in its lower end, upon opposite sides, are formed twoslot-s, in which ICO the short pivoted levers V are placed and whichhave their outer ends shaped as shown for the purpose of catching in agroove that is made in the plugger-point. The upper ends of these leversare connected by a semicircular spring b, which keeps their outer endspressed closely together. When the plugger-point T is struck, it isforced outward a slight distance, and then, owing to the pressure of theouter ends of the levers V in the groove W in the side of thepluggerpoint, the point is forced back into position. When it is desiredto remove this pluggerpoint, it is only necessary to press against theinner ends of the levers V with one hand and draw the plugger-point outwith the other.

By means of the construction here shown it will be seen that all of theoperating parts are inclosed, so as to protect them from dust and dirtand to prevent them from injuring the person using the mallet, that thepluggerpoint can be quickly removed and another substituted in itsplace, and that a direct blow can be given to the plugger-point.

Having thus described my invention, I claiml. In a dental tool, arevolving shaft carrying a cam, a mallet having a yoke which has alateral movement in relation to the shaft and an opening in which thecam revolves, and a means for holding the said yoke in the path traveledby the cam, the parts combined substantiallyas described.

2. In a dental tool, a revolving shaft carrying a cam, a block journaledupon the shaft, a mallet having a yoke which slides upon the said blockand an opening in which the cam revolves, and a spring between the saidblock and the yoke for normally holding the latter in the path traveledby the cam, the parts combined substantially as set forth.

In a dental tool, a revolving shaft carrying a cam, a mallet mounted tohave a lateral movement upon the shaft and an opening in which the camrevolves for the purpose described, and a pivoted lever in the pathtraveled by the cam, which returns the mallet back to position after ablow has been delivered, the parts combined substantially as described.

In testimony whereof I aflix my signature in presence of two witnesses.

HENRY CARLISLE HINCHMAN.

Witnesses:

U. G. BARNES, y ULYssEs BITTNER,

